1. Field of the Invention
The invention pertains to apparatus for automatically feeding envelopes or other discrete pieces of sheet material to automatic or manual printing apparatus and for receiving the printed material from the printing apparatus for storage in a magazine.
2. Description of the Prior Art
Methods and apparatus for serially feeding envelopes and other sheet material to a printer are known and evermore widely used in connection with programmable printing machines such as automatic typewriters or so called word processing systems. Efforts have been made to develop apparatus which can selectively feed two or more types of material such as envelopes and forms or letterheads. Generally, such devices have become unduly complicated, are too cumbersome to be conveniently mounted on and removed from printers such as automatic and manual typewriters, and require interfacing with the controls of the printer itself. There are many applications for feeding apparatus for printing machines which require that only one type of envelope or form be fed during a particular printing operation.
Moreover, it is desired in many applications of envelope and sheet material feeders that the feeder be readily adaptable to be used in conjunction with printers manufactured by different concerns and having different drive mechanisms and controls. Accordingly, it is important to be able to provide an envelope feeder which is substantially self contained and is easily converted from use with one type of printer to use with another type of printer. An envelope feeder meeting the aforementioned criteria should also be compact, light-weight and portable to the extent so as to provide for relative ease in moving the feeder apparatus from one printer to another. Furthermore, prior art feeding apparatus are also characterized by being dependent on the controls of the printer for operation to feed the envelope or the like in properly timed relation to the printer platen operation. This control interfacing requires that the feed apparatus controls be specially adapted for each type of printer. This makes the feeding apparatus unduly complicated or even impossible to build for use with more than one specific type of printer.
In addition to the problems associated with prior art envelope feeding apparatus as regards portability and versatility there are also deficiencies that have not been entirely overcome regarding proper timing and separation of the serially fed envelopes or sheets, uncomplicated feed paths for the material being fed to and from the printer, proper alignment of the envelopes or sheets on entering the printer platen, and ease of correcting a jammed condition should one occur. These problems as well as other deficiencies that have been associated with prior art feeding apparatus have been overcome with the present invention.